ABSTRACT Developing new strategies to address pain in patients with opioid use disorder (OUD) is critical to improving outcomes for the large population of patients with comorbid chronic pain and OUD. With the national opioid epidemic, which has been propelled by overuse of opioids for pain, efforts are underway to increase access to medication assisted treatment (MAT), especially with the medication buprenorphine. However, many individuals who receive MAT leave treatment early and continue to struggle with opioid use, often within the context of poorly-managed comorbid chronic pain. New strategies to help patients cope with and adapt to chronic pain are urgently needed. Psychosocial interventions for pain have been effective in patients with chronic pain and substance use disorders, but these interventions have not been examined in the OUD population receiving MAT. Our team received a SAMHSA State Targeted Response to Opioid Crisis grant to help providers increase delivery of MAT in Southeast Michigan. Providing alternative pain treatment options has the potential to be an important component delivering effective MAT. The purpose of this study is to refine and adapt a psychosocial pain management intervention (PPMI) to be delivered by telephone for patients with OUD receiving MAT and then to conduct a randomized controlled trial of the intervention in patients receiving MAT to improve OUD adherence and pain- and substance-related outcomes. The intervention uses elements of cognitive behavioral pain management interventions adapted specifically for patients with OUD receiving MAT. This new intervention will be compared to an enhanced usual care condition (EUC). The study will recruit 100 patients with OUD and comorbid pain receiving MAT in clinics in southeast Michigan. The specific aims are: R21 Specific Aim 1: Using qualitative patient interviews, adapt a telephone-based PPMI and enhanced usual care (EUC) condition to address the needs of individuals with pain and OUD receiving MAT. R21 Specific Aim 2: Iteratively refine the PPMI and EUC informed (1) by beta-testing with patients with OUD and chronic pain and (2) by expert opinion. R33 Specific Aim 1: Conduct a pilot RCT comparing a telephone-based PPMI approach (n=50) to EUC (n=50) to assess the impact of randomization to PPMI on retention to MAT (primary outcome). R33 Specific Aim 2: Determine the impact of the PPMI on pain level, pain-related functioning, and frequency of opioid use (secondary outcomes). Knowledge generated in this study will have important implications for improving outcomes for patients with OUD and chronic pain through increased understanding of effective patient-focused psychosocial strategies to help patients better manage pain. Ultimately, this line of research has the potential to lead to reductions in morbidity and mortality among the large number of patients suffering from OUD and chronic pain.